Abstract
Background: Abdominal aortic aneurysm is the 10th leading cause of death representing 1.3% of all fatalities among men aged 65-85 in the Western countries. Screening procedures are available, but the cost-effectiveness for Norway is unknown.
Objective: To predict the costs and impact on life expectancy of an AAA screening program.
Methods: A Markov model was developed to compare the effect of a single ultrasound screening for a cohort of men at the age 65 with the current no screening strategy. The following health states were included: AAA¡Ü30 mm, AAA30¨C39 mm, AAA40¨C54 mm, AAA55-59 mm, AAA¡Ý60 mm with risk factors, AAA>60 mm with unknown risk factors, Inoperable AAA55-59 mm, Inoperable AAA¡Ý60 mm , Post EVAR (patients who survive endovascular repair will transit to this health state after repair), Dead from aneurysm and Dead from other causes. Transition probabilities were derived from the medical literature and the cycle length was one year. Incremental cost per life year gained was calculated and sensitivity analysis and discounting of future effects were performed.
Outcome measures: The results are expressed as incremental costs, incremental life years gained and cost per life year gained.
Results: The average life time AAA-related cost of a 65-year-old patient in the non-screening group was NOK3010 (NOK2032 discounted) and in the screening group NOK6074 (NOK4686 discounted), resulting in incremental costs of NOK2654 per screened patient. The life expectancy was 16.3832 (11.7051 discounted) for non-screened patients and 16.4351 (11.7345 discounted) for screened, or a life year gained of 0.0294. The cost per life year gained was NOK90300.
The results of the one-way sensitivity analyses indicate that the conclusion is not threatened by any realistic change of the model input.
Interpretation/conclusion: One-time ultrasonography screening for AAA men at the age 65 appears to be cost-effective.